Superorder ACROTHORACICA Gruvel, 1905

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Superorder ACROTHORACICA Gruvel, 1905

Boring Barnacles

Compiler and date details

15 March 2012 - Gary C. B. Poore, Museum Victoria

Introduction

The Acrothoracica, one of three superorders of the Cirripedia, are small burrowing barnacles found largely in marine carbonate sediments and 'shells' of marine invertebrates such as molluscs, corals or echinoderms. The body, lacking its own calcareous shell, is usually only a couple of millimetres long. The cavity in which it lives opens to the exterior via a narrow slit. Four to six cirri are present and extend through the slit when feeding. Tomlinson (1969) and Newman (1996) comprehensively reviewed acrothoracican biology, anatomy and systematics. Their ordinal arrangement is no longer followed. About 66 species are recognised worldwide.

Martin & Davis (2001) treated the Acrothoracica Gruvel, 1905 as a superorder of the Infraclass Cirripedia with two orders, Pygophora (with two families) and Apygophora (with one). Until recently this arrangement has been widely followed. Kolbasov (2009), in the latest comprehensice review, rearranged the three families differently, again into two orders Lithoglyptida (for Lithoglyptidae and Trypetesidae) and Cryptophialida (for Cryptophialidae) (see Newman 2011 for summary).

Tomlinson (1969) diagnosed all taxa then known. His family diagnoses are reproduced here. While Kolbasov & Newman (2005) recognised differences between the families they provided clear diagnoses only of the three subfamilies of Lithoglyptidae.

Dates of publication and availability of Gerstaecker's and Utinomi's works

Gerstaecker edited and contributed to the "Fünfter Band, erste Abtheilung. Crustacea (Erste Hälfte)" of Bronn's Klassen und Ordnungen des Thier-Reichs ... with the dates 1866-1879 on the title page. According to Peter Dworschak, Natural History Museum, Vienna, "in our copy, someone has scribbled with pencil the date of receipt on the bottom page of each new consignment (Lieferung)". The date on the Lieferung, pp. 625-672, dealing with Acrothoracica is 1870 which is therefore the date of publication of his new family Cryptophialidae.

Utinomi published three works in 1950. Mark Grygier, Lake Biwa Museum, viewed copies of all works at the University of Kyoto.

The first work, in Nakamura's book, in Japanese, was issued on 1 April 1950 according to a bookplate pasted to the inner side of the end-paper of the copy in the plant genetics library. Whether or not this work constitutes an available publication has been questioned. While Utinomi stated that his descriptions would be published in other papers he "decided to make detailed examination of these two acrothoracid species and [he] studied in detail the structure and development of internal organs, which consequently revealed that they belonged to so far unrecorded new species in a new genus. Not only this (they belong to new species in a new genus), [he got] many new findings about the anatomical morphology of Acrothoracida and recognised that the previous classification system should be drastically revised." [Translation by J. Kojima] In the view of ICZN Commissioners Mark Grygier and Junichi Kojima, this does not meet the requirements of ICZN Articles 8.2 or 8.3 which allow for works and names to be disclaimed.

Utinomi's other works in 1950 appeared in Memoirs of the College of Science, Kyoto (Imperial) University Ser. B. The copy of the relevant issue at the Library of Biological Science still retained the original cover of issue No. 3, in which the two papers were published. Publishing information is on the inside back cover: the printing date was 20 July 1950, and the date of issue was 25 July 1950.

Following these investigations it is possible to confirm that the names in Utinomi's contribution to Nakamura's Some problems of modern biology have seniority over his later publication of the same names.

Acknowledgements

The compiler thanks Peter Dworschak, Natural History Museum, Vienna, for acertaining the date of publication of Gerstaecker's work, and Mark Grygier, Lake Biwa Museum, and Shigeyuki Yamato, Seto Marine Biological Laboratory, for obtaining Utinomi's works. I thank Mark Grygier for determining the exact dates of publication of Utinomi's publications and thank him and his fellow ICZN Commissioner Junichi Kojima for their opinions on the availabilty of names.